Curve Fitting and other apps don't show panels

I am using Matlab 2019b. My apps somehow seem to be broken such that they don't show any panels. Cftool for instance, only shows the following-

Upon closing the cftool, a blank window appears and it is a loop of closing the blank window and it appearing again when I try to close cftool. There are no error message or warnings in the command window. I had the same issue with Matlab 2018b and have since uninstalled-reinstalled multiple times. Somehow the apps seem broken for my computer. Any suggestions?

[Kavya Vuriti]

Is this the same issue with other apps? Try restoring default path using the following commands.

>> restoredefaultpath
>> savepath

Now restart MATLAB and try rehashing toolbox cache.

>> rehash toolboxcache